A pulmonary embolus is a blockage of an artery in the lungs. The most common cause of the blockage is a blood clot.
A pulmonary embolus is most often caused by a blood clot that develops in a vein outside the lungs. The most common blood clot is one in a deep vein of the thigh or in the pelvis (hip area). This type of clot is called a deep vein thrombosis (DVT). The blood clot breaks off and travels to the lungs where it lodges.
Less common causes include air bubbles, fat droplets, amniotic fluid, or clumps of parasites or tumor cells.
You are more likely to get this condition if you or your family has a history of blood clots or certain clotting disorders. A pulmonary embolus may occur:
After heart attack, heart surgery, or stroke
After severe injuries, burns, or fractures of the hips or thigh bone
After surgery, most commonly bone, joint, or brain surgery
During or after a long plane or car ride
If you have cancer
If you take birth control pills or estrogen therapy
Long-term bed rest or staying in one position for a long time
Disorders that may lead to blood clots include:
Diseases of the immune system that make it harder for the blood to clot.
Inherited disorders that make the blood more likely to clot. One such disorder is antithrombin III deficiency.
Main symptoms of a pulmonary embolism include chest pain that may be any of the following:
Under the breastbone or on one side
Sharp or stabbing
Burning, aching, or a dull, heavy sensation
Often gets worse with deep breathing
You may bend over or hold your chest in response to the pain
Other symptoms may include:
Dizziness, lightheadedness, or fainting
Low oxygen level in blood (hypoxemia)
Fast breathing or wheezing
Fast heart rate
Leg pain, redness, or swelling
Low blood pressure
Sudden cough, possibly coughing up blood or bloody mucus
Shortness of breath that starts suddenly during sleep or on exertion
Low grade fever
Bluish skin (cyanosis) -- less common
How well a person recovers from a pulmonary embolus can be hard to predict. It often depends on
What caused the problem in the first place (for example, cancer, major surgery, or an injury)
The size of the blood clot in the lungs
If the blood clot dissolves over time
Some people can develop long-term heart and lung problems.
Death is possible in people with a severe pulmonary embolism.
Blood thinners may be prescribed to help prevent DVT in people at high risk, or those who are undergoing high-risk surgery.
If you had a DVT, your provider will prescribe pressure stockings. Wear them as instructed. They will improve blood flow in your legs and reduce your risk for blood clots.
Moving your legs often during long plane trips, car trips, and other situations in which you are sitting or lying down for long periods can also help prevent DVT. People at very high risk for blood clots may need shots of a blood thinner called heparin when they take a flight that lasts longer than 4 hours.
Do not smoke. If you smoke, quit. Women who are taking estrogen must stop smoking. Smoking increases your risk of developing blood clots!